The world wide web inventor Tim Berners-Lee is calling for a “fight” against hacking and abuse on its 30th birthday.

A CNN article by Rob Picheta reported that Berners-Lee has called for global efforts to tackle state-sponsored hacking, criminal behavior and abusive language on the internet, in an open letter marking the 30th anniversary of the revolutionary technology.

Tim Berners-Lee acknowledged that “many people feel afraid and unsure if the web is really a force for good,” in a letter published for his World Wide Web Foundation on Monday.

“While the web has created opportunity, given marginalized groups a voice, and made our daily lives easier, it has also created opportunity for scammers, given a voice to those who spread hatred, and made all kinds of crime easier to commit,” the letter added.

Berners-Lee, who has previously rallied for improvements to the technology, said the “fight for the web is one of the most important causes of our time.” He added: “You can’t just blame one government, one social network or the human spirit….To get this right, we will need to come together as a global web community.”

The computer scientist submitted his first proposal for an “information management system” on March 12, 1989, plans that his boss called “vague but exciting.”

Thirty years later, around half the world’s population is online, but tech giants that dominate the internet, including Google, Facebook and Twitter, have been criticized in recent years for failing to stem the spread of misinformation and harassment on their platforms.

Berners-Lee identified three major “sources of dysfunction” affecting the web: deliberate malicious intent, system design and unintended negative consequences of benevolent design.

The first, he said, resulted from issues like state-sponsored hacking and criminal behavior; the second from entities like ad-based revenue models “that commercially reward clickbait and the viral spread of misinformation”; and the last produced problems such as “the outraged and polarized tone and quality of online discourse.”

He urged governments, companies and citizens to “ensure the other half (of the world) are not left behind offline, and that everyone contributes to a web that drives equality, opportunity and creativity.”

Berners-Lee launched a campaign called “Contract for the Web” at the Web Summit tech conference in Lisbon, Portugal, last year.

More than 50 companies and organizations, including Facebook, Google and the French government have signed the contract, which will be published in full in May 2019.

Read the complete text of Berners-Lee’s letter here.